- definitions: virulence and all that
- transmission modes
- tradeoff theory
- beyond the tradeoff theory
17 October 2016
Q: which of these represent virulence?
virulence depends on both host and parasite
tolerance (host)
Parasites evolve lower virulence over time for the good of the species; don't want to hurt host
Given enough time a state of peaceful coexistence usually becomes established between any host and parasite … throughout nature, infection without disease is the rule rather than the exception (Dubos, 1980)
For nature, survival of the species is all that counts (Macfarlane Burnet & White, 1972)
virgin-soil epidemics
what other factors might explain virulence of new outbreaks?
counterexamples: malaria, tuberculosis …
Modes of transmission may drive parasite evolution
what's your prediction about nosocomial (hospital-borne) transmission?
Wikipedia, Richard Harvey
Bottom line: myxomavirus probably still reduces populations somewhat, but the Australians are looking for other biocontrol solutions (calicivirus).
Maximizing \(R_0\):
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